This Exhaust System is often purchased with the Stone Exhaust BMW B58 Catless Performance Downpipe (Inc. M140i, M240i, 440i, 540i, 740i & X5 M40i) or the Stone Exhaust BMW B58 Eddy Catalytic Performance Downpipe (Inc. M140i, M240i, 440i, 540i, 740i & X5 M40i)

You may wish to add the Stone Valvetronic System (Singe Valve) which enables you to control the valves remotely via the stone remote controller.

Stone Exhaust Cat-Back Exhaust System 

(340i & 440i)

OPF Delete

R&D and 3D Scanning

Stone Exhaust engineers use reverse engineering by 3D scanning OEM parts to understand their functionality and identify weaknesses. Data has been collected continuously in order to analyze factors such as pipe diameter, route and degrees of the bending angles of the Exhaust System found on the BMW B58 F30 F32 340i & 440i. 

During R&D, Stone Exhaust utilizes the 3D simulation software to stimulate the exhaust gas flow movement, thermal and pressure rise zone. Progressive improvements were continually made until the optimal performance was achieved.

7 Axis CNC Bending Machine

Stone Exhaust System are constructed utilizing a 7 axis CNC Bending Machine which is the ultimate machine for high levels of precision delivery, necessary for industries such as the aerospace and defense industries.

With the state-of-the-art bending machine, Stone Exhaust has achieved the industry’s standard to an impressive 98% roundness, whilst maintaining the wear of the outer bore at only 25% at 180°. Airflow obstruction and welding fracture problems are prevented by utilizing this technology. With the combination of the CNC Bending machine, Reverse Engineering and 3D Design Scanning, Stone exhaust has created an integrally molded exhaust pipe with an accuracy error under 0.025mm.

Crisscross and Overlapping Welding Technique

The flange between the turbo and the downpipes reaches extreme temperatures (800℃ to 1100℃) which creates stress on the connection point. By utilizing both welding techniques to increases the width and penetration of welds. This increases the endurance and tolerance of these connection points, leading to quality products with reliable performance.

Direct Spot Welding

Our highly skilled engineers perform direct spot welding to increase product strength. This is undertaken by mechanical welding arms, proven to achieve greater precision and penetration in their welds compared to manual welding, resulting in an end product that is a work of art.

Features

• STONE Valvetronic BMW B58 F30 F32 340i & 440i. 
• OEM Integration
• Plug and Play OBDII controller
• One Piece Design
• Machine Welding
• In House Research and Development
• 3D Scanning & Reverse Engineering

Compatibility - B58 Engine

BMW 3 Series

• F30 LCI/F31LCI 340i/340i xDrive (2014-2018)

BMW 4 Series 

• F32/F32 LCI 440i/440i xDrive (2015-2017)
• F33 440i (2015-2017)/440i xDrive (2013-2017)
• F33 LCI 440i/440i xDrive (2016-2018)
• F36 440i/440i xDrive (2015-2017)
• F36 LCI 440i/440i xDrive (2016-2018)

Warranty

Stone Exhaust 2 Year Warranty

Manufactured by

Stone Exhaust

Part Number

AP514B58 (Dual Exit with Twin Tailpipes / Require original Bumper)

AP514QB58 (Dual Exit with Quad Tailpipes / Require M Sport bumper)